Extractors used for removal of spent cartridge cases from the cartridge chambers of a revolver cylinder, referred to herein as “cylinder bores” or “bores,” are generally in the form of an extractor plate mounted adjacent one end of a tubular stem. The extractor plate typically has a plurality of radially extending arms equally spaced apart and defining, between each adjacent pair of arms, a cylindrical, concave, radiused surface that conforms to the shape of a bore of the cylinder. The radiused surfaces are adapted to fit under and engage the rims of cartridge cases disposed in the cylinder bores.
Prior art extractor plates fit within a recess in the rear surface of the revolver cylinder. The recess typically has a depth that is approximately equal to the thickness of the extractor plate. As the extractor plate fits within the recess in the cylinder, the concave, radiused surfaces of the plate form part of the bores in which the cartridges are disposed. Typically, the recess also includes edge portions adapted to conform to the shape of the outer perimeter of the extractor plate. In prior art extractor designs, such as in U.S. Pat. No. 5,218,148, herein incorporated by reference in its entirety, the ends of the extractor arms that define the outer perimeter of the extractor plate fit in a contiguous parallel relationship with the upright edges which define the perimeter of the recess. This contiguous parallel relationship limits the rotation of the extractor plate.
Although prior art extractors have proven extremely reliable, it is possible that prior art designs may provide insufficient contact between the extractor and the rim of the cartridge case creating the possibility of an angular misalignment of the extractor with the cartridge. Additionally, prior art extractors may have difficulty extracting rim fire cartridges as such cartridges are thin walled and have the tendency to expand against the cylinder bores under the pressures generated during firing. Such expansion could potentially make extraction difficult as the prior art extractor plates form part of the cylinder bores.
In light of the above, an object of the present invention is to provide an improved extractor for revolvers by increasing the contact area between the extractor and the cartridge.
An additional object of the present invention is to provide an improved extractor for rim fire ammunition. This object is accomplished by providing an extractor that does not form part of the cylinder bores and engages only the rim of the cartridge. The bores are entirely disposed within the cylinder thereby allowing the rim fire case to expand outwardly upon firing without affecting the extractor.
This and other objects and advantages of this invention will be more readily appreciated from a reading of the application in conjunction with the drawings annexed hereto as follows.